As disclosed in British Patent 1,185,111 (Morris) and U.S. Pat. Nos. 2,082,275 (Daimler et al.), 3,555,079 (Marumo et al.), and 4,832,871 (Bade), it is known that tert-amines can be quaternized with haloalkanoate salts in water or a polar aprotic solvent to prepare betaines in solution form, most commonly as 30-35% active aqueous solutions.
Solid betaines have the advantages over betaine solutions that they can be transported at lower costs and offer more flexibility in the formulation of products from betaines. It is possible to recover solid betaines from the solutions, but it would be preferable to be able to prepare the betaines directly in solid form.
Copending application Ser. No. 07/652,617 (Perine et al.), now U.S. Pat. No. 5,075,498, discloses a process whereby betaines are prepared in solid form by reacting tert-amines with haloalkanoate salts in polar aprotic solvents in which the betaines are substantially insoluble. This process is a commercially-attractive method of producing betaines. However, when it is used to prepare a substantially pure betaine, it requires the use of centrifugation, crystallization, and drying steps which add to its cost.